1. Field of the Invention
The present invention relates to a score verification system and a score verification method for an online game, the system and method verifying that the score of a player who has played an online game is a true score.
2. Description of the Related Art
with the wide spread of broadband communication technology in recent years, the use of online games has rapidly grown. Various types of online games have become popular, such as, e.g., competition games where plural players play a match against each other through a network, or games of the type where plural players challenge the same game and compete for high score. In the online games noted above, attempts have been made by unscrupulous individuals, or groups of individuals to unfairly obtain a high score by altering the game through hacking, or the like, or by through falsification of the high score. In order to allow players to enjoy a game by allowing them to compete for high score under fair conditions, it is desirable to prevent such unfair acts.
In an attempt to address the above problem, Unexamined Japanese Patent Publication No. 2002-355445 teaches, for example, a system in which the result of a game is encrypted and is transmitted to a game server in order to prevent the falsification of a score. In addition, Unexamined Japanese Patent Publication No. 2004-65956 teaches a system where at the time of transmission/reception of a game session, an encryption key is transmitted/received in order to prevent alterations from being made by another device on a network.
The foregoing methods for preventing the alteration of a score, or the alteration of the game, have as their main object to prevent attack by hacking or the like from another device on a network. Thus, there is a problem that, for example, if reverse engineering is performed in a terminal operated by a player, and if thereby the player found a method of transmitting a score altered by some method to a server, it is impossible to verify that the score has been altered.
That is, only a countermeasure to ensure that a score is safely transmitted to a server from a player terminal is insufficient to prevent an unfair act. Instead, a countermeasure to ensure that the score itself to be transmitted to the server is a true score obtained from the result of operation of a game actually executed by the player should be the score taken as the actual score.